1. Field of the Invention
The present invention is directed to a system that allows users to point at objects within a volumetric display system, and, more particularly to a system that allows a number of different pointing approaches and pointing tools.
2. Description of the Related Art
A class of three-dimensional (3D) displays, called volumetric displays, is currently undergoing rapid advancement. The types of displays in this class include holographic displays, swept volume displays and static volume displays. Volumetric displays allow for three-dimensional (3D) graphical scenes to be displayed within a true 3D volume. That is, a volumetric display is not a projection of volumetric data onto a 2D display but a true physical 3D volume. Such displays can take many shapes including cylinders, globes, domes, cubes, etc. with a dome being a typical shape. Because the technology of these displays is undergoing rapid development those of skill in the art are concentrating on the engineering of the display itself. As a result, the man-machine interface to or the ways in which people interface with these types of displays is receiving scant attention.
While the volumetric displays allow a user to view different parts of a true 3D scene, the act of viewing the different parts typically requires that the user physically move around (or over) the display or that the display be moved or rotated in front of the user. As the display moves relative to the user, graphical objects may also move relative to the user. When the display is relatively stationary or when it is relatively moving, the user may need to interact with the display by pointing to something, such as a model object to, for example, paint the object, or to select the object for some function such as to move the object or select a control on an interface of the object. The object to which the user needs to point may be at any level within the display from the surface of the display adjacent the enclosure to the farthest distance within the display from the enclosure or the user. As a result, the user needs a mechanism for pointing to objects at different locations within a volumetric display. Today, those in the field do not appear to be concerned with this problem. Because many computer users are familiar with conventional interface tools and techniques, what is needed is a mechanism that will allow users to point at objects within the volumetric display in a situation where the viewpoint changes and that takes advantage of the learned behavior of users with respect to two-dimensional (2D) display interfaces, such as the 2D mouse driven cursor.